PARIS
— Two traces of red ocher on a rock face were the first signs that this cave was more than a hole in a wall. Then, a red bear, a reindeer, a slouching hyena, a woolly rhinoceros, mammoths, buffaloes, horses, mountain goats, lions, owls, and a spotted panther. In all, explorers found about 300 animals and birds and as many engravings, painted or etched in ocher and charcoal at least 17,000 years ago. The hyena is only the second found in a prehistoric cave painting; the panther and owl had never been seen before.

The three explorers who discovered these painted caverns Dec. 24 sensed the importance of what they had found. Leader Jean-Marie Chauvet was a guard of prehistoric sites for the French Ministry of Culture. His companions, Christian Hillaire and Eliette Brunel-Deschamps, were amateur explorers. When they saw the painted figures, they shouted for joy.

The world's archaeological community is now joining them. Last week's announcement of the discovery of a rich collection of cave paintings near the town of Vallon-Pont d'Arc in the Ardeche region in southern France is being described as one of the archaeological finds of the century. ``This is one of the most beautiful paleolithic sites in the world ... a very great work of art,'' says Jean Clottes, France's leading expert on cave paintings and one of the first to see the site after its discovery. ``The only cave that compares with this one is Lascaux [in the Dordogne region of France].''

The underground site includes several vast caverns measuring up to 70 meters by 40 meters (230 feet by 131 feet) linked by wide corridors. Some 50 groupings of animals, varying from 1/2 meter to 4 meters long (20 inches to 13 feet), along with symbolic signs and hand prints, are painted or etched on the walls. In one group, two woolly rhinos face off; in another, two lionesses in profile lead a hunt with an intensity of expression that would drop a reindeer at 10 paces. In one of the most noted clusters, four parallel paintings suggest the motion of a horse lifting its head.

Scientists who visited the site also remark on the sophisticated use of the surface of rock faces in the design of individual animals and groupings - a dimension that can't be picked up from studying flat reproductions.

``The quality of this site is altogether remarkable, both in terms of the animals that are rarely seen and the quality of the soils,'' says Jean-Philippe Rigaud, director of the National Center of Prehistory of Perigueux. ``Most prehistoric sites are badly preserved.''

The Ardeche caves were effectively sealed off by a rock slide soon after the paintings were completed, leaving the soils and the placement of objects in caverns and passageways intact. Analysis of soils could yield new information about climate, plants, and wildlife; the age of the paintings; tools and materials used to make them; and even the purpose of the site. A bear skull found on a pile of rocks in the center of one chamber, for example, could be part of a religious ritual.

The caves at Lascaux were also well-preserved when first discovered in 1940. But the impact of 1 million visitors - between 1945 when the site was opened to the public and 1964 when it closed - seriously eroded the quality of the paintings.

Daniel DeBaye, now director of tourism in Dordogne, was in charge of building a scale replica of the Lascaux caves to meet public demand to see the paintings. ``When you open a prehistoric-cave site to the public, you put all at risk,'' he says. The replica, Lascaux 2, opened in 1983, and 4 million people have visited it since.

The Lascaux case was very much on the minds of the three Ardeche explorers and French government officials, who kept the discovery a secret until the caves could be protected from public incursions.

``It is critical above all to preserve the site,'' said French Minister of Culture Jacques Toubon when he announced discovery of the site last week. A system of television surveillance has already been set up. The Ministry of Culture says it will take a year just to equip the caves with walkways and detectors to preserve the environment before the real scientific work can begin. The ministry also is convening a scientific council to develop a plan to study the site. A key concern: how to provide public access.

``We're looking into what it means to give the public access, almost virtual access, to the cave. This could take five to 10 years,'' said Michel Kneubuhler, the ministry's regional spokesman in charge of the site. ``Meanwhile, we're planning a video of the site and will use more traditional methods to respond to the first questions from the public in the months to come.''

The ministry is considering building either a ``virtual reality'' or a multimedia model of the new site, a technique developed by Electricite de France to map activity in the core of a nuclear reactor. Both techniques are already being tried to map a recently discovered underwater site of cave paintings in Cosquer, near Marseille, but neither has yet produced a satisfactory level of precision in mapping irregular rock surfaces.

One question for scientists will be whether the site is authentic. Rock-art specialist Clottes insists that the site has already passed tests, including the presence of a patina of translucent limestone and breaks in the clarity of painted lines (clear lines are suspect as they do not allow for aging). Clottes also notes that one group of paintings near the top of one cavern appears to have been accomplished by standing on a shelf of rock, long since caved in. To forge these paintings would have required a ladder, and there are no traces of ladders evident in the site.

``It would be thrilling to study that site,'' says Norbert Aujoulat, a researcher at the National Center of Prehistory of Perigueux who has done much of his work at Lascaux. ``There's great interest in a site that has not changed since paleolithic times. You can see traces of activities other than what you see on a wall.''

Many archaeologists are interested in whether the ``sanctuary structure'' or thematic sequences of animals in the new site follow the patterns developed by the late Andre Leroi-Gourhan, whose pioneering work in the 1960s and '70s is still the core reference for students of cave art.

This new site is sure to test old theories and inspire new ones. Are cave paintings connected to hunting rituals? Are the patterns of animals random or in response to a deeper religious logic? If so, what god is being worshiped and why?